Fluid couplings normally consist of interconnectable parts or halves each including connection means, such as nut structure, threads, snap locks, locking balls, or similar conventional devices. The fact that the connection means is directly carried by the coupling parts assures alignment of the coupling parts and will maintain a leak proof interconnection as long as the connecting means remains in the locked or coupling position.
In special applications it is sometimes desired that a plurality of fluid couplings be mounted upon a common support defining a plural conduit system manifold whereby proper positioning of the support permits a plurality of coupling halves to simultaneously sealingly mate with a like plurality of interengaging coupling halves to complete a plurality of conduit systems. Such installations are used in the petroleum exploration and drilling arts, of instance, wherein the aforedescribed interconnection of a plurality of conduit systems are used to power hydraulic tools and may take place under submerged conditions several hundred feet below the ocean's surface in offshore drilling rigs. Under such adverse conditions close supervision and adjustment of individual couplings is not possible. In such installations the support member may be lowered into position relative to a fixed support member to align the coupling parts mounted on each support member, and once aligned the support members are moved toward each other to permit coupling of the complimentary coupling parts. The maintaining of the relationship of the support members may be achieved by large coupling locks, however, because of manufacturing tolerances, inconsistencies in coupling parts installation, slight misalignment of the support members, or the inability to achieve accurate position of the support members, slight misalignments may occur in the mating coupling components resulting in leakage. Such leakage, especially of petroleum products, has adverse environmental impact, is in violation of environmental laws, and is not acceptable. Leakage is especially likely to occur where the sealing between coupling halves is accomplished through metal-to-metal seals, as are often used in high pressure fluid systems.
It is an object of the invention to provide a self-aligning fluid coupling for use with a support member manifold wherein the mounting of a coupling half upon the support member permits a limited degree of relative movement between the coupling half and support member for self-aligning purposes without adversely affecting efficiency of the completed fluid coupling.
Another object of the invention is to provide a self-aligning fluid coupling having a half mounted within a support member wherein the mounted coupling half is capable of limited axial and radial movement with respect to the support member, and axial movement is through a resilient biasing system producing sufficient force to maintain a sealed relationship between metal-to-metal seals.
In the practice of the invention the self sealing coupling halves are mounted on relatively large support members adapted to be moved toward and away from each other. For instance, one support member may constitute a stationary manifold fixed relative to a foundation, well installation or other structure, and a movable support member may constitute a manifold which is lowered toward the fixed manifold, and each manifold support member includes a plurality of conduit systems associating with the coupling halves mounted on the support members. As the movable support member approaches the fixed member the plurality of couplings simultaneously interengage wherein fluid communication between mating coupling halves exists upon the support members achieving the intended final positioning relative to each other.
As each support member, or manifold, includes a plurality of coupling halves, and as slight misalignments may exist with respect to the mating coupling halves one of the coupling halves, in accord with the invention, is provided with self-aligning means to compensate for inaccuracies or misalignments wherein an effective, leakproof, metal-to-metal sealing occurs between interconnected couplings.
The coupling sealing ends of the halves include annular radial surfaces for abutting an annular seal ring, and, usually, each coupling half will include a self-sealing valve, usually of the poppet type, which are mutually engageable during connection of the coupling halves and fully automatically opened upon the coupling being completed. The support members containing the self-aligning coupling half includes a bore receiving the coupling half, the diameter of the bore being slightly greater than the diameter of the coupling half portion received therein wherein limited relative radial movement is permitted. Annular resilient rings circumscribe the coupling half within the bore resiliently centering the coupling half therein, yet permitting relative radial displacement for alignment purposes.
The coupling half is also axially slidable within the support member bore for axial self-aligning movement, and a biasing unit which consists of a plurality of Belleville washers is mounted upon the coupling for imposing a high axial force on the coupling half sufficient to overcome fluid pressures within the coupling endeavoring to reduce the sealing forces. The presence of the biasing structure permits an effective interconnection between the mating coupling parts regardless of misalignment occurring between the support members, or the couplings mounted upon the support members.